Dileucine and Resistance Training Adaptations (DTS)

A Pilot Study to Examine Changes in Resistance Training Adaptations After Leucine and Dileucine Ingestion

This study seeks to compare the observed changes in resistance training adaptations after supplementation of isomolar amounts of leucine or dileucine in healthy resistance-trained men. This will provide a better understanding of supplementation with leucine versus dileucine over a 10-week period in regards to increasing muscular performance.

Study Overview

• Status: Completed
• Conditions: Hypertrophy; Strength Training Adaptations; Weight-Bearing Strengthening Program
• Intervention / Treatment: Dietary supplement: Placebo; Dietary supplement: Leucine; Dietary supplement: Dileucine

Detailed Description

The study will be conducted using a randomized, double-blind approach with individuals being provided daily 2-gram doses of leucine, 2-gram doses of dileucine, or a placebo. Daily blinded supplementation will occur each day for a 10-week period of time while completing a heavy resistance training program. Participants follow the resistance training program for a total of 10 weeks. To compare the efficacy of leucine in form of amino acid or dipeptide supplementation on resistance training adaptations, changes in fat-free, lean, and fat mass will be determined using a 4-compartment body composition model. Skeletal muscle cross-sectional area will be assessed using ultrasound. Maximal strength, muscular endurance, and power will also be assessed. Participants will be required to provide weekly compliance and complete one supervised workout per week. After 2, 6, and 10 weeks of following the supplementation and resistance training regimens, participants will return to the laboratory to complete testing bouts consisting of identical assessments of body composition, muscular strength, muscular endurance, lower-body power, and anaerobic capacity. Adverse events related to each supplementation group will be recorded and assessed.

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Saint Charles, Missouri, United States, 63301
      • Exercise and Performance Nutrition Laboratory

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Male
• Between the ages of 18-39 years of age
• Currently participating in resistance training exercise

Exclusion Criteria:

• Female
• Participants who are determined to not be weight stable defined as week 0 and week 2 body mass levels deviating by 3% or more.
• Any individual who is currently being treated for or diagnosed with a cardiac, respiratory, circulatory, musculoskeletal, metabolic, immune, autoimmune, psychiatric, hematological, neurological or endocrinological disorder or disease.
• Body mass index > 25 kg/m2. Individuals with a body mass index greater than 25 kg/m2, but a body fat percentage less than 25% fat will be accepted into the study
• Individuals who present with any previous injury or illness that would prevent them from appropriately completing all exercise lifts.
• Participants who are not able to fit onto the DEXA table will not be able to participate in the research due to size restrictions of the equipment. This typically includes individuals exceeding 400 pounds or those greater than 6'4".
• Those individuals with less than 12 months of structured resistance training experience will be excluded from the study.
• Individuals whose maximal relative upper body strength is below 1.0 will be excluded.
• Individuals whose maximal relative lower body strength is below 1.5 will be excluded.
• All participants who DO NOT abstain from taking any additional forms of nutritional supplementation deemed to be ergogenic or that will impact resistance training adaptations (pre-workouts, creatine, beta-alanine, etc.) for four weeks prior to beginning this study and for the entire duration of the study.
• Individuals who are currently using or have used within the past 12 months anabolic-androgenic steroids.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Participants will supplement daily for 10 weeks with 2 grams rice flower placebo in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.	Dietary supplement: Placebo; Participants will supplement daily for 10 weeks with 2 grams rice flower placebo in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.
Active Comparator: Leucine; Participants will supplement daily for 10 weeks with 2 grams rice leucine in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.	Dietary supplement: Leucine; Participants will supplement daily for 10 weeks with 2 grams leucine in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.
Experimental: Dileucine; Participants will supplement daily for 10 weeks with 2 grams dileucine (RAMPS, Ingenious Ingredients, TX, USA) in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.	Dietary supplement: Dileucine; Participants will supplement daily for 10 weeks with 2 grams dileucine (RAMPS, Ingenious Ingredients, TX, USA) in capsule form. On training days, participants will consume their assigned supplement within 60 minutes of completing their workout. On non-training days, participants will consume their assigned supplement with their first meal of the day. All doses will be consumed with 8-12 ounces of water.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fat-Free Mass	Fat-free mass will be determined via Dual-Energy X-Ray Absorptiometry	10 weeks
Leg Press 1RM	Leg Press 1RM will be measured using the leg press (lower-body) exercise.	10 weeks
Bench Press 1RM	Bench Press 1RM will be measured using the bench press (upper-body) exercise.	10 weeks
Maximal Isometric Mid-Thigh Pull Force Production	Maximal Isometric Mid-Thigh Pull Force Production will be measured using an isometric mid-thigh pull test	10 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fat Mass	Fat mass will be determined via Dual-Energy X-Ray Absorptiometry	10 weeks
Lean mass	Lean mass will be determined via Dual-Energy X-Ray Absorptiometry	10 weeks
% Body Fat	% Body Fat will be determined via Dual-Energy X-Ray Absorptiometry	10 weeks
Total body water	Total Body Water will be determined via bioelectrical impedance analysis	10 weeks
Extracellular Body Water	Extracellular Body Water will be determined via bioelectrical impedance analysis	10 weeks
Intracellular Body Water	Intracellular Body Water will be determined via bioelectrical impedance analysis	10 weeks
Skeletal muscle cross-sectional area	Skeletal muscle cross-sectional area will be measured using ultrasound measurements of the participants thigh muscles.	10 weeks
Bench Press Repetitions to Fatigue	Bench Press repetitions to fatigue will be measured using the bench press (upper-body) exercises on four separate occasions (visits 2, 3, 4, and 5). To complete this assessment, study participants will use a load that corresponds to 80% of their Visit 2 1RM for bench press exercise and will be instructed to complete as many repetitions as they can until failure for one set of each exercise. Failure will be defined as resting for more than two seconds throughout any point on the exercise set or technique failure.	10 weeks
Leg Press Repetitions to Fatigue	Leg Press repetitions to fatigue will be measured using the leg press (lower-body) exercises on four separate occasions (visits 2, 3, 4, and 5). To complete this assessment, study participants will use a load that corresponds to 80% of their Visit 2 1RM for leg press exercise and will be instructed to complete as many repetitions as they can until failure for one set of each exercise. Failure will be defined as resting for more than two seconds throughout any point on the exercise set or technique failure.	10 weeks
Peak Anaerobic Power	Peak Anaerobic Power will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass	10 weeks
Mean Anaerobic Power	Mean Anaerobic Power will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass	10 weeks
Rate of Fatigue	Rate of Fatigue will be measured using a Wingate Anaerobic Test lasting 30-seconds at a load set to 7.5% of week 0 body mass	10 weeks
Maximal Concentric Rate of Force Development	Maximal concentric rate of force development will be measured using a countermovement jump performed on a force plate	10 weeks

Collaborators and Investigators

• Sponsor: Lindenwood University
• Collaborators: Ingenious Ingredients, L.P.
• Investigators: Principal Investigator: Chad M Kerksick, PhD, Lindenwood University

Study record dates

Study Major Dates

• Study Start (Actual): May 7, 2021
• Primary Completion (Actual): June 29, 2023
• Study Completion (Actual): June 29, 2023

Study Registration Dates

• First Submitted: November 2, 2023
• First Submitted That Met QC Criteria: November 2, 2023
• First Posted (Actual): November 8, 2023

Study Record Updates

• Last Update Posted (Actual): November 8, 2023
• Last Update Submitted That Met QC Criteria: November 2, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Keywords: Exercise; Peptides; Dietary Supplements; Dipeptide; Adaptations
• Additional Relevant MeSH Terms: Pathological Conditions, Anatomical; Hypertrophy
• Other Study ID Numbers: IRB-41-64

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No plan to make individual participant data available to other researchers

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No